With Cushy Stock you can upload one image to multiple sites with the Cushy Stock Lite version.
After uploading close the program, start it again and upload the next image.
Not very useful when you want to upload a lot of files. Very time consuming.
With Filezilla it seems that you can schedule your uploads. Try this topic: How to schedule uploads with filezilla by greener.
Otherwise use the Search option to find that topic.
Filezilla is freeware.